/* =============================================
   大发彩票站 — 全站共享样式 /assets/site.css
   ============================================= */

/* ---------- 0. Reset ---------- */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
  overflow-x: hidden;
  scroll-padding-top: calc(var(--header-h-m) + 1rem);
}

body {
  min-height: 100vh;
  font-family: var(--font-body);
  font-weight: 400;
  line-height: 1.75;
  letter-spacing: 0.01em;
  background: var(--c-cream);
  color: var(--c-ink);
  -webkit-font-smoothing: antialiased;
}

img,
svg,
video {
  display: block;
  max-width: 100%;
  height: auto;
}

ul,
ol {
  list-style: none;
}

a {
  color: var(--c-red);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

button {
  font: inherit;
  color: inherit;
  background: none;
  border: none;
  cursor: pointer;
}

input,
select,
textarea {
  font: inherit;
}

/* ---------- 1. CSS 变量 ---------- */
:root {
  --c-gold: #E6B31E;
  --c-red: #9E1C2C;
  --c-blue: #0A2E4A;
  --c-purple: #5A2A82;
  --c-cream: #FDF6E3;
  --c-ink: #1A1A1A;
  --c-muted: #5C5C5C;

  --grad-gold: linear-gradient(135deg, #E6B31E, #D98E04);
  --grad-red: linear-gradient(135deg, #9E1C2C, #6D1420);
  --grad-face: linear-gradient(120deg, #E6B31E, #9E1C2C, #5A2A82);

  --font-heading: "Noto Serif SC", "Songti SC", serif;
  --font-body: "Noto Sans SC", "PingFang SC", sans-serif;
  --font-data: "JetBrains Mono", "Sarasa Mono SC", monospace;

  --sidebar-w: 288px;
  --sidebar-w-c: 88px;
  --header-h-m: 64px;
  --content-max: 1280px;
  --pad: 1.25rem;

  --border-thick: 3px;
  --border-thin: 1px;
  --shadow-box: 6px 6px 0 rgba(10, 46, 74, 0.25);
  --shadow-heavy: 8px 8px 0 rgba(10, 46, 74, 0.35);
  --shadow-card: 5px 5px 0 rgba(158, 28, 44, 0.15);

  --radius-lg: 16px;
  --radius-md: 10px;
  --radius-sm: 6px;

  --tr-fast: 0.2s ease;
  --tr-med: 0.35s ease;
  --tr-slow: 0.6s ease;
}

/* ---------- 2. 基础排版 ---------- */
h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-heading);
  font-weight: 900;
  letter-spacing: 0.02em;
  line-height: 1.25;
  color: inherit;
}

p {
  margin-bottom: 1rem;
}

::selection {
  background: var(--c-gold);
  color: var(--c-blue);
}

/* ---------- 3. 焦点可见 ---------- */
:focus {
  outline: none;
}

:focus-visible {
  outline: 3px solid var(--c-gold);
  outline-offset: 2px;
  border-radius: 4px;
}

/* ---------- 4. 主内容 ---------- */
#main-content {
  min-height: 60vh;
  scroll-margin-top: calc(var(--header-h-m) + 1rem);
  outline: none;
}

/* ---------- 5. 跳转链接 ---------- */
.skip-link {
  position: fixed;
  top: -120px;
  left: 0;
  z-index: 9999;
  background: var(--grad-gold);
  color: var(--c-blue);
  font-weight: 700;
  font-size: 0.875rem;
  padding: 0.75rem 1.5rem;
  border-radius: 0 0 var(--radius-md) 0;
  box-shadow: 3px 3px 0 rgba(0, 0, 0, 0.25);
  transition: top var(--tr-fast);
  text-decoration: none;
  min-width: 160px;
}

.skip-link:focus,
.skip-link:focus-visible {
  top: 0;
  outline: none;
  color: var(--c-blue);
  text-decoration: none;
}

/* ---------- 6. 布局 ---------- */
.content-container {
  width: 100%;
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 2rem var(--pad);
}

@media (min-width: 768px) {
  .content-container {
    padding: 3rem 2rem;
  }
}

#main-content {
  display: block;
}

/* ---------- 7. 头部 — 桌面侧栏 ---------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  width: var(--sidebar-w);
  background: var(--c-blue);
  background-image:
    radial-gradient(circle at 30% 70%, rgba(90, 42, 130, 0.22), transparent 55%),
    radial-gradient(circle at 80% 20%, rgba(230, 179, 30, 0.08), transparent 50%);
  z-index: 300;
  display: flex;
  flex-direction: column;
  color: var(--c-cream);
  transition: width var(--tr-med);
  border-right: var(--border-thick) solid rgba(230, 179, 30, 0.4);
  overflow: visible;
}

.site-header::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 6px;
  background: var(--grad-face);
  z-index: 1;
}

/* ---------- 8. 头部 — 移动顶栏 ---------- */
@media (max-width: 1023px) {
  html {
    scroll-padding-top: calc(var(--header-h-m) + 1rem);
  }

  .site-header {
    width: 100%;
    height: var(--header-h-m);
    bottom: auto;
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    border-right: none;
    border-bottom: 3px solid var(--c-gold);
    padding: 0 1rem;
  }

  .site-header::before {
    height: 4px;
  }

  .header-inner {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
  }

  .site-nav {
    position: fixed;
    top: var(--header-h-m);
    left: 0;
    bottom: 0;
    width: min(320px, 85vw);
    background: var(--c-blue);
    background-image: linear-gradient(135deg, rgba(90, 42, 130, 0.2), transparent 60%);
    border-right: 3px solid var(--c-gold);
    transform: translateX(-105%);
    transition: transform var(--tr-med);
    z-index: 320;
    padding: 1.5rem 1rem;
    overflow-y: auto;
    overflow-x: hidden;
    box-shadow: none;
  }

  .site-nav[data-open] {
    transform: translateX(0);
    box-shadow: 8px 0 30px rgba(0, 0, 0, 0.35);
  }

  .nav-collapse {
    display: none !important;
  }

  body {
    margin-left: 0 !important;
  }
}

@media (min-width: 1024px) {
  html {
    scroll-padding-top: 1rem;
  }

  body {
    margin-left: var(--sidebar-w);
    transition: margin-left var(--tr-med);
  }

  html.nav-collapsed body {
    margin-left: var(--sidebar-w-c);
  }

  .header-inner {
    flex-shrink: 0;
    padding: 1.5rem 1rem 1rem;
  }

  .site-nav {
    flex: 1;
    padding: 0.75rem 1rem 1.25rem;
    overflow-y: auto;
    overflow-x: hidden;
  }
}

/* ---------- 9. 品牌 ---------- */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.875rem;
  color: var(--c-cream);
  text-decoration: none;
  min-width: 0;
}

.brand:hover,
.brand:focus-visible {
  text-decoration: none;
}

.brand-emblem {
  width: 50px;
  height: 50px;
  border-radius: 12px;
  background: var(--grad-face);
  position: relative;
  overflow: hidden;
  flex-shrink: 0;
  border: 2px solid rgba(253, 246, 227, 0.35);
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.35), inset 0 0 12px rgba(253, 246, 227, 0.15);
}

.brand-emblem::before {
  content: '';
  position: absolute;
  left: 50%;
  bottom: -10px;
  width: 30px;
  height: 30px;
  background: var(--c-blue);
  transform: translateX(-50%) rotate(45deg);
  border-radius: 6px;
}

.brand-emblem::after {
  content: '';
  position: absolute;
  top: 9px;
  left: 50%;
  transform: translateX(-50%);
  width: 16px;
  height: 13px;
  background: rgba(253, 246, 227, 0.92);
  border-radius: 50% 50% 42% 42%;
  box-shadow:
    inset 0 -3px 0 rgba(10, 46, 74, 0.3),
    -9px 3px 0 -2px rgba(230, 179, 30, 0.95),
    9px 3px 0 -2px rgba(230, 179, 30, 0.95);
}

.brand-copy {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
  min-width: 0;
}

.brand-name {
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: 1.35rem;
  letter-spacing: 0.04em;
  background: var(--grad-gold);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: var(--c-gold);
  white-space: nowrap;
}

.brand-tag {
  font-size: 0.75rem;
  letter-spacing: 0.3em;
  color: rgba(253, 246, 227, 0.5);
  text-transform: uppercase;
}

@media (max-width: 1023px) {
  .brand {
    gap: 0.625rem;
  }

  .brand-emblem {
    width: 40px;
    height: 40px;
    border-radius: 10px;
  }

  .brand-emblem::after {
    top: 7px;
    width: 13px;
    height: 11px;
    box-shadow:
      inset 0 -2px 0 rgba(10, 46, 74, 0.3),
      -7px 2px 0 -2px rgba(230, 179, 30, 0.95),
      7px 2px 0 -2px rgba(230, 179, 30, 0.95);
  }

  .brand-name {
    font-size: 1.1rem;
  }

  .brand-tag {
    font-size: 0.625rem;
    letter-spacing: 0.2em;
  }
}

@media (max-width: 480px) {
  .brand-emblem {
    width: 36px;
    height: 36px;
  }

  .brand-name {
    font-size: 1rem;
  }

  .brand-tag {
    display: none;
  }
}

/* ---------- 10. 导航 ---------- */
.nav-list {
  display: flex;
  flex-direction: column;
  gap: 0.375rem;
}

.nav-link {
  display: flex;
  align-items: center;
  gap: 0.875rem;
  padding: 0.75rem 0.875rem;
  color: rgba(253, 246, 227, 0.72);
  border-radius: var(--radius-md);
  border: var(--border-thin) solid transparent;
  border-left: 4px solid transparent;
  font-weight: 500;
  font-size: 0.925rem;
  text-decoration: none;
  transition:
    background var(--tr-fast),
    color var(--tr-fast),
    border-color var(--tr-fast),
    transform var(--tr-fast);
}

.nav-link:hover,
.nav-link:focus-visible {
  color: var(--c-cream);
  background: rgba(230, 179, 30, 0.1);
  border-color: rgba(230, 179, 30, 0.3);
  text-decoration: none;
  transform: translateX(3px);
}

.nav-link[aria-current="page"] {
  color: var(--c-gold);
  background: rgba(230, 179, 30, 0.12);
  border-left: 4px solid var(--c-gold);
  font-weight: 700;
}

.nav-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  flex-shrink: 0;
  border-radius: var(--radius-sm);
  background: rgba(230, 179, 30, 0.1);
  border: 1px solid rgba(230, 179, 30, 0.25);
  color: var(--c-gold);
  font-size: 0.9rem;
  font-weight: 700;
  transition:
    background var(--tr-fast),
    color var(--tr-fast),
    transform var(--tr-fast);
}

.nav-link[aria-current="page"] .nav-icon {
  background: var(--c-gold);
  color: var(--c-blue);
  border-color: var(--c-gold);
  transform: rotate(-6deg);
}

.nav-label {
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* ---------- 11. 导航折叠按钮 ---------- */
.nav-collapse {
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.875rem 1rem;
  background: rgba(230, 179, 30, 0.06);
  color: rgba(253, 246, 227, 0.65);
  border-top: 1px solid rgba(253, 246, 227, 0.12);
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  transition:
    background var(--tr-fast),
    color var(--tr-fast);
}

.nav-collapse:hover,
.nav-collapse:focus-visible {
  background: rgba(230, 179, 30, 0.14);
  color: var(--c-gold);
}

.nav-collapse-icon {
  display: inline-block;
  font-size: 1.1rem;
  line-height: 1;
  transition: transform var(--tr-med);
}

.site-header[data-collapsed] .nav-collapse-icon {
  transform: rotate(180deg);
}

.site-header[data-collapsed] .nav-collapse-text {
  display: none;
}

/* 桌面折叠状态 */
@media (min-width: 1024px) {
  .site-header[data-collapsed] {
    width: var(--sidebar-w-c);
  }

  .site-header[data-collapsed] .brand-copy {
    display: none;
  }

  .site-header[data-collapsed] .brand {
    justify-content: center;
    padding: 0.5rem 0;
  }

  .site-header[data-collapsed] .nav-label {
    display: none;
  }

  .site-header[data-collapsed] .nav-link {
    justify-content: center;
    padding: 0.5rem 0.25rem;
    border-left-width: 3px;
  }

  .site-header[data-collapsed] .nav-link:hover {
    transform: none;
  }

  .site-header[data-collapsed] .nav-icon {
    width: 40px;
    height: 40px;
  }

  .site-header[data-collapsed] .nav-collapse {
    padding: 1rem 0;
  }
}

/* ---------- 12. 移动导航按钮 ---------- */
.nav-toggle {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: transparent;
  border: 2px solid rgba(230, 179, 30, 0.6);
  border-radius: var(--radius-sm);
  padding: 0.5rem 0.75rem;
  color: var(--c-gold);
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  transition:
    background var(--tr-fast),
    border-color var(--tr-fast);
  min-height: 40px;
}

.nav-toggle:hover,
.nav-toggle:focus-visible {
  background: rgba(230, 179, 30, 0.15);
  border-color: var(--c-gold);
}

.nav-toggle-icon {
  width: 20px;
  height: 16px;
  position: relative;
  display: inline-block;
  flex-shrink: 0;
}

.nav-toggle-icon > span,
.nav-toggle-icon::before,
.nav-toggle-icon::after {
  content: '';
  position: absolute;
  left: 0;
  width: 100%;
  height: 2px;
  background: currentColor;
  border-radius: 2px;
  transition:
    transform var(--tr-fast),
    top var(--tr-fast),
    opacity var(--tr-fast);
}

.nav-toggle-icon > span {
  top: 7px;
}

.nav-toggle-icon::before {
  top: 0;
}

.nav-toggle-icon::after {
  top: 14px;
}

.nav-toggle[aria-expanded="true"] .nav-toggle-icon > span {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] .nav-toggle-icon::before {
  top: 7px;
  transform: rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-icon::after {
  top: 7px;
  transform: rotate(-45deg);
}

.nav-toggle-text {
  display: none;
}

@media (max-width: 1023px) {
  .nav-toggle {
    display: inline-flex;
  }
}

@media (min-width: 1024px) {
  .nav-toggle {
    display: none;
  }
}

/* ---------- 13. 页脚 ---------- */
.site-footer {
  position: relative;
  background: var(--c-blue);
  background-image:
    radial-gradient(circle at 85% 15%, rgba(90, 42, 130, 0.2), transparent 55%),
    radial-gradient(circle at 10% 90%, rgba(230, 179, 30, 0.06), transparent 45%);
  color: var(--c-cream);
  margin-top: 4rem;
  border-top: 6px solid var(--grad-face);
  padding-top: 0;
}

.site-footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 6px;
  background: var(--grad-face);
  z-index: 1;
}

.site-footer::after {
  content: '大';
  position: absolute;
  right: 2rem;
  bottom: 5rem;
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: 10rem;
  line-height: 1;
  color: rgba(230, 179, 30, 0.04);
  pointer-events: none;
  z-index: 0;
}

.footer-inner {
  position: relative;
  z-index: 1;
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 3rem 2rem 2.5rem;
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1.2fr;
  gap: 2.5rem;
}

.footer-col {
  min-width: 0;
}

.footer-brand-col .brand {
  margin-bottom: 1.25rem;
}

.footer-about {
  color: rgba(253, 246, 227, 0.65);
  font-size: 0.9rem;
  line-height: 1.75;
}

.footer-heading {
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: 1rem;
  letter-spacing: 0.08em;
  color: var(--c-gold);
  margin-bottom: 1.1rem;
  padding-bottom: 0.5rem;
  position: relative;
}

.footer-heading::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 36px;
  height: 3px;
  background: var(--grad-face);
  border-radius: 2px;
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
}

.footer-links a {
  color: rgba(253, 246, 227, 0.72);
  font-size: 0.9rem;
  text-decoration: none;
  transition:
    color var(--tr-fast),
    padding-left var(--tr-fast);
}

.footer-links a:hover,
.footer-links a:focus-visible {
  color: var(--c-gold);
  padding-left: 5px;
  text-decoration: none;
}

.footer-contact-list {
  display: flex;
  flex-direction: column;
  gap: 0.625rem;
  font-size: 0.875rem;
  color: rgba(253, 246, 227, 0.65);
}

.footer-contact-item {
  display: flex;
  align-items: flex-start;
  gap: 0.5rem;
  line-height: 1.6;
  word-break: break-all;
}

.footer-contact-item::before {
  content: '›';
  color: var(--c-gold);
  font-weight: 700;
  flex-shrink: 0;
}

.footer-bottom {
  position: relative;
  z-index: 1;
  border-top: 1px solid rgba(253, 246, 227, 0.12);
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 1.5rem 2rem;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
}

.footer-icp {
  font-family: var(--font-data);
  font-size: 0.8125rem;
  color: rgba(253, 246, 227, 0.5);
  white-space: nowrap;
}

.footer-trust {
  font-size: 0.8125rem;
  color: rgba(253, 246, 227, 0.45);
  max-width: 760px;
  text-align: right;
  line-height: 1.6;
  margin: 0;
}

@media (max-width: 1023px) {
  .footer-inner {
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    padding: 2.5rem 1.5rem 2rem;
  }

  .footer-bottom {
    padding: 1.25rem 1.5rem;
    flex-direction: column;
    text-align: center;
  }

  .footer-trust {
    text-align: center;
  }
}

@media (max-width: 640px) {
  .footer-inner {
    grid-template-columns: 1fr;
    gap: 1.75rem;
    padding: 2rem 1.25rem;
  }

  .site-footer::after {
    font-size: 6rem;
    right: 1rem;
    bottom: 4rem;
  }
}

/* ---------- 14. 返回顶部 ---------- */
.back-top {
  position: fixed;
  bottom: 1.5rem;
  right: 1.5rem;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--grad-gold);
  color: var(--c-blue);
  border: 3px solid var(--c-blue);
  box-shadow: 4px 4px 0 rgba(10, 46, 74, 0.3);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  cursor: pointer;
  z-index: 600;
  opacity: 0;
  visibility: hidden;
  transform: translateY(16px);
  transition:
    opacity var(--tr-med),
    transform var(--tr-med),
    visibility var(--tr-med),
    background var(--tr-fast);
}

.back-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-top:hover,
.back-top:focus-visible {
  background: var(--c-gold);
  color: var(--c-blue);
}

@media (max-width: 640px) {
  .back-top {
    bottom: 1rem;
    right: 1rem;
    width: 42px;
    height: 42px;
  }
}

/* ---------- 15. 通用按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.875rem 1.75rem;
  font-family: var(--font-body);
  font-size: 0.9375rem;
  font-weight: 700;
  line-height: 1.4;
  text-decoration: none;
  border-radius: var(--radius-md);
  border: var(--border-thick) solid transparent;
  cursor: pointer;
  transition:
    transform var(--tr-fast),
    box-shadow var(--tr-fast),
    background var(--tr-fast),
    color var(--tr-fast),
    border-color var(--tr-fast);
}

.btn:hover,
.btn:focus-visible {
  text-decoration: none;
}

.btn-primary {
  background: var(--grad-gold);
  color: var(--c-blue);
  border-color: var(--c-blue);
  box-shadow: 4px 4px 0 rgba(10, 46, 74, 0.35);
}

.btn-primary:hover,
.btn-primary:focus-visible {
  transform: translate(2px, 2px);
  box-shadow: 2px 2px 0 rgba(10, 46, 74, 0.35);
  background: #E6B31E;
}

.btn-outline {
  background: transparent;
  color: var(--c-red);
  border-color: var(--c-red);
}

.btn-outline:hover,
.btn-outline:focus-visible {
  background: var(--c-red);
  color: var(--c-cream);
}

/* ---------- 16. 卡片 ---------- */
.card {
  background: #fff;
  border: var(--border-thick) solid var(--c-blue);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  box-shadow: var(--shadow-card);
  transition:
    transform var(--tr-fast),
    box-shadow var(--tr-fast);
  position: relative;
}

.card:hover {
  transform: translate(-3px, -3px);
  box-shadow: var(--shadow-heavy);
}

.card--gold {
  background: linear-gradient(135deg, #FFF9E3, #FBE9B7);
  border-color: var(--c-gold);
}

.card--red {
  background: linear-gradient(135deg, #F9E4E8, #F3CDD3);
  border-color: var(--c-red);
}

.card--dark {
  background: var(--c-blue);
  border-color: var(--c-gold);
  color: var(--c-cream);
}

.card--purple {
  background: linear-gradient(135deg, #F0EAF7, #E0D3EC);
  border-color: var(--c-purple);
}

.card-title {
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: 1.25rem;
  margin-bottom: 0.625rem;
}

.card-text {
  color: var(--c-muted);
  font-size: 0.9125rem;
  line-height: 1.65;
  margin-bottom: 0;
}

.card--dark .card-text {
  color: rgba(253, 246, 227, 0.72);
}

.card--dark .card-title {
  color: var(--c-gold);
}

/* ---------- 17. 栅格 ---------- */
.grid {
  display: grid;
  gap: 1.5rem;
}

.grid--2 {
  grid-template-columns: repeat(2, 1fr);
}

.grid--3 {
  grid-template-columns: repeat(3, 1fr);
}

@media (max-width: 1023px) {
  .grid--3 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 640px) {
  .grid--2,
  .grid--3 {
    grid-template-columns: 1fr;
  }
}

/* ---------- 18. 版块标题 ---------- */
.section-title {
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: clamp(1.5rem, 3vw, 2.25rem);
  line-height: 1.2;
  color: var(--c-ink);
  margin-bottom: 1rem;
  padding-left: 1.1rem;
  position: relative;
}

.section-title::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.22em;
  bottom: 0.22em;
  width: 6px;
  background: var(--grad-face);
  border-radius: 4px;
}

.section-subtitle {
  color: var(--c-muted);
  font-size: 1rem;
  margin-bottom: 2rem;
  max-width: 680px;
}

/* ---------- 19. 页面标题 ---------- */
.page-heading {
  position: relative;
  margin-bottom: 2.5rem;
  padding-bottom: 1.5rem;
}

.page-heading::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 80px;
  height: 5px;
  background: var(--grad-face);
  border-radius: 3px;
}

.page-heading-title {
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: clamp(2.125rem, 4.5vw, 3.5rem);
  line-height: 1.1;
  color: var(--c-red);
  margin-bottom: 0.75rem;
}

.page-heading-desc {
  color: var(--c-muted);
  font-size: 1rem;
  max-width: 640px;
  margin-bottom: 0;
}

/* ---------- 20. 面包屑 ---------- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.375rem;
  font-size: 0.8125rem;
  color: var(--c-muted);
  padding: 0.75rem 0;
  margin-bottom: 1rem;
}

.breadcrumb-item {
  display: flex;
  align-items: center;
}

.breadcrumb-item + .breadcrumb-item::before {
  content: '›';
  margin-right: 0.375rem;
  color: var(--c-gold);
  font-weight: 700;
}

.breadcrumb-item a {
  color: var(--c-red);
  text-decoration: none;
}

.breadcrumb-item a:hover {
  text-decoration: underline;
}

/* ---------- 21. 图片容器 ---------- */
.image-frame {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: var(--border-thick) solid var(--c-blue);
  box-shadow: var(--shadow-card);
  background: var(--c-blue);
  aspect-ratio: 4 / 3;
  display: block;
}

.image-frame--wide {
  aspect-ratio: 16 / 9;
}

.image-frame--portrait {
  aspect-ratio: 3 / 4;
}

.image-frame--soft-border {
  border-color: var(--c-gold);
}

.image-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--tr-slow);
}

.image-frame:hover img {
  transform: scale(1.03);
}

.image-frame::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, rgba(230, 179, 30, 0.06), rgba(158, 28, 44, 0.04), rgba(90, 42, 130, 0.08));
  pointer-events: none;
}

/* ---------- 22. 数据统计块 ---------- */
.stat-block {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  padding: 1.25rem;
  background: var(--c-blue);
  border-radius: var(--radius-md);
  border-left: 5px solid var(--c-gold);
  color: var(--c-cream);
  box-shadow: 4px 4px 0 rgba(10, 46, 74, 0.15);
}

.stat-label {
  font-size: 0.8125rem;
  color: rgba(253, 246, 227, 0.6);
  letter-spacing: 0.08em;
}

.stat-value {
  font-family: var(--font-data);
  font-size: 1.625rem;
  font-weight: 700;
  color: var(--c-gold);
  line-height: 1.2;
}

.stat-unit {
  font-size: 0.8125rem;
  color: rgba(253, 246, 227, 0.5);
  margin-left: 0.25rem;
}

/* ---------- 23. 提示框 ---------- */
.callout {
  padding: 1.25rem 1.5rem;
  border-radius: var(--radius-md);
  margin: 1.5rem 0;
  font-size: 0.925rem;
  line-height: 1.7;
  position: relative;
}

.callout--warning {
  background: #FFF9E8;
  border: 2px solid var(--c-gold);
  border-left: 6px solid var(--c-gold);
  color: var(--c-ink);
}

.callout--info {
  background: #EAF2F9;
  border: 2px solid var(--c-blue);
  border-left: 6px solid var(--c-blue);
  color: var(--c-ink);
}

.callout--danger {
  background: #FBEAEC;
  border: 2px solid var(--c-red);
  border-left: 6px solid var(--c-red);
  color: var(--c-ink);
}

/* ---------- 24. 数据表格 ---------- */
.data-table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  font-family: var(--font-data);
  font-size: 0.875rem;
  background: #fff;
  border: var(--border-thick) solid var(--c-blue);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.data-table th,
.data-table td {
  padding: 0.8125rem 1rem;
  text-align: left;
  border-bottom: 1px solid rgba(10, 46, 74, 0.08);
}

.data-table th {
  background: var(--c-blue);
  color: var(--c-gold);
  font-weight: 700;
  letter-spacing: 0.04em;
  font-family: var(--font-body);
  border-bottom: 2px solid rgba(230, 179, 30, 0.4);
}

.data-table tbody tr:nth-child(even) td {
  background: rgba(230, 179, 30, 0.04);
}

.data-table tbody tr:hover td {
  background: rgba(230, 179, 30, 0.09);
}

.data-table tbody tr:last-child td {
  border-bottom: none;
}

.data-table .num-highlight {
  color: var(--c-gold);
  font-weight: 700;
}

.data-table .num-alert {
  color: var(--c-red);
  font-weight: 700;
}

/* ---------- 25. 脸谱渐变分隔线 ---------- */
.face-divider {
  height: 5px;
  background: var(--grad-face);
  border: none;
  border-radius: 3px;
  margin: 2.5rem 0;
}

/* ---------- 26. 研究板 ---------- */
.research-board {
  background: #fff;
  background-image: repeating-linear-gradient(
    rgba(10, 46, 74, 0.03) 0,
    rgba(10, 46, 74, 0.03) 1px,
    transparent 1px,
    transparent 28px
  );
  border: var(--border-thick) solid var(--c-blue);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  padding: 1.75rem;
  position: relative;
}

.research-board::before {
  content: '研究板';
  position: absolute;
  top: -14px;
  left: 1rem;
  background: var(--c-gold);
  color: var(--c-blue);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  padding: 0.15rem 0.875rem;
  border-radius: 4px;
  border: 2px solid var(--c-blue);
}

/* ---------- 27. 滚动显现 ---------- */
[data-reveal] {
  opacity: 0;
  transform: translateY(28px);
  transition:
    opacity var(--tr-slow),
    transform var(--tr-slow);
  will-change: opacity, transform;
}

[data-reveal][data-revealed] {
  opacity: 1;
  transform: translateY(0);
}

[data-reveal-delay="1"] {
  transition-delay: 0.08s;
}

[data-reveal-delay="2"] {
  transition-delay: 0.16s;
}

[data-reveal-delay="3"] {
  transition-delay: 0.24s;
}

[data-reveal-delay="4"] {
  transition-delay: 0.32s;
}

/* ---------- 28. 桌面适配 ---------- */
@media (min-width: 1024px) {
  .site-header {
    /* 侧栏无需额外处理 */
  }

  .footer-inner {
    grid-template-columns: 1.5fr 1fr 1fr 1.3fr;
  }
}

/* ---------- 29. 动画降级 ---------- */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    transition-delay: 0s !important;
  }

  [data-reveal] {
    opacity: 1 !important;
    transform: none !important;
  }

  .back-top {
    transition: none;
  }

  .nav-toggle-icon > span,
  .nav-toggle-icon::before,
  .nav-toggle-icon::after {
    transition: none;
  }

  .nav-link {
    transition: none;
  }
}